1 I/2017 UI Oumuamua

thoughts: an elongated massive body spinning fast, possibly with high iron content ,--fits what requirements? : interstellar travel. spin: artificial gravity at the extremities, iron? magnetic shielding. alternative theory: , it was launched with enough energy to reach us, good aim, near 1AU. but is waiting for us to snag it next time around, because it does not have the retrorocket, decellerating capacity. prototype for us to use on the return trip. move to alternate or humour.

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Spin rate, 1 rotation per 7.3 hrs. Not what I would call spinning fast. With an estimated length of 400 meters, tumbling end to end would produce an artificial gravity effect of 0.00000117g at the extremities.

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thanks for the details I was not aware of. What are any such elongated asteroids? catch them hollow, tunnel them out, spin them up for space stations! or hitch a ride on it the next pass back to where it came from.

Caves at the ends would give you some shelter, perhaps with inside water jackets, a solid iron-rich body would withstand faster rotation, and be a ready made magnet to provide radiation shielding. Snagging the next one, and being prepared would allow to leave the solar system with already build in velocity of a massive body. far fetched? yes, but it came from far away. Potential hitchhikers in a galaxy. an almost ready made ride, thumbs up. If we could do it, they could have.too
The interior could be stuffed with life forms or their seeds, that have proven to be viably dormant in space together with info that betters the packages on the 2 voyageurs.
Would not theoretically a close path to a gravity well modify the trajectory to result in an eventual return?

The tendency at the extremities would be to be flung off it, not to be attracted more. Centrifugal force.

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That would depend, right? If it is tumbling end-over-end, I think you could conceivably stand on the end, with your feet/boots opposing the direction of spin, & get a modicum of pressure on the soles of your boots, that might approximate a bit of gravity. It would be a fine balance, though. Lean too far 'outboard' & you get an unintended long trip of your own.

That would depend, right? If it is tumbling end-over-end, I think you could conceivably stand on the end, with your feet/boots opposing the direction of spin, & get a modicum of pressure on the soles of your boots, that might approximate a bit of gravity. It would be a fine balance, though. Lean too far 'outboard' & you get an unintended long trip of your own.

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No. The force you would feel would be parallel to the long axis, not perpendicular to it. i.e. you will be clinging to the side of a vertical surface.

No. The force you would feel would be parallel to the long axis, not perpendicular to it. i.e. you will be clinging to the side of a vertical surface.

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Imagine a spinning propeller, with you standing on the windward side. The known rotational period should not result in a significant centripetal force, letting the acceleration come mainly from contact with the surface itself ( lift if you will). At least that's what I'm thinking. It would not be great in any event.

Spin rate, 1 rotation per 7.3 hrs. Not what I would call spinning fast. With an estimated length of 400 meters, tumbling end to end would produce an artificial gravity effect of 0.00000117g at the extremities.

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If it is to make the "alien cosmonauts" comfortable, they must be really fragile, but : that spin rate is within ~25 % of~ 90% of the spinning mass in our planetary system. movement shared. waltzing to the same rhythm.

Imagine a spinning propeller, with you standing on the windward side. The known rotational period should not result in a significant centripetal force, letting the acceleration come mainly from contact with the surface itself ( lift if you will). At least that's what I'm thinking. It would not be great in any event.

Centrifugal force (what you experience on the asteroid) is aligned with the centre of rotation - i.e. parallel to the long axis.

I'm trying to think of some simple experiments you do could to prove it to yourself. A phonograph record, a bicycle tire, a board tied to a string, spun around you. Yes, even a propellor. Anything you place on the propellor will get flung off the end of the propellor.

That is the force you experience while on the asteroid - the force appears to emanate from the centre of rotation, directly outward long a radius.

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And countered by the strength of the material. There are many proposals to create artificial gravity via rotation of spacecraft, a good one: a massive service module , lead shielded reactor even, having a tethered living module rotating a long way off, (minimal coriolis effects). The outward force you describe, would be experienced by any object inside, part of that tumbling cucumber* and be experienced as pressure against the inside periphery, or tension in the tether of that spacecraft.*tumbling coincidentally at nearly the same rate as most of our system's planetary mass.